This is so cheap and easy, it's nearly cheesy.
This will show you how to reliably photograph lightning for under 3 dollars.

Step 1: Professional Lightning Photography

Lightning photography is some of the most impressive natural/landscape photography there is. Most photographers use high-end cameras with adjustable f-stops, special films, a nice tripod, and a cable shutter release. These are all well and good but even the film is out of my price range.

So first, buy yourself a disposable camera. I used a 1000 speed "high action" camera (because it was the cheapest at ~$2.30) and the results seem to hint that a slower speed would work better (those that developed were flooded with light) and I'll tell you how it goes.

RESULTS: the picture in the Intro was taken with a 400 speed camera. Worked great, especially since the photo was taken at dusk.

A word of warning: After experimenting with Kodak disposables, I've found they don't work the same way. They use a spring trigger, which doesn't fit the following steps. I'd stick with fujifilm (plus, they are generally cheaper)

Step 2: Open It Up

Rip off the paper covering to the camera. Try to keep it one piece so you can put it back on when you get it developed (I don't know if this is necessary, but the guy developing your film may want to know what speed it is.)

There are clips on the sides and top of the camera that releases the front. Use a coin, screwdriver, scissors, etc. to pop these open and take off the front. Be careful not to pop off the back or bottom, exposing the film.

When you open it, the lens will probably fly out, so don't tell me you haven't been warned.

Step 3: Find the Shutter

Now examine the mechanics of the camera. Carefully push around the fragile pieces until you find the little lever that opens the shutter. If you can't, smile and press the trigger, and watch to see what moves when the shutter opens. In my camera, it was shaped like a little thumb.

Step 4: Making Your "cable Trigger Release"

Now you'll need about 6 inches of thread. I used very thin fishing line (which, regrettably, is very hard to see in these pictures). Make a slipknot and drop it over the little "thumb" that opens the shutter. Most of these cameras have a little hole near the sight on the back of the camera, and put the other end of the thread through there. If your camera doesn't have a hole, drill one.

Pull lightly on the thread to make sure it will open the shutter all the way. I hooked the thread around a post inside the camera to ensure it pulled from the right angle.

Close back up your camera. Remember to put back on the lens that flew under the couch when you opened it up.

Step 5: Now Wait...

Now that you have your camera with a string coming out of the back of it, all you need is a storm. And hopefully at night, for reasons we'll see in a moment.

When the time comes, hold the camera down against something sturdy (I used a window sill) and point it towards the source of lightning. Now pull your string taught (the shutter opens). Wait for it... and when you get a flash of lightning, release the string to close the shutter. If you try this during the day, ambient light will flood the camera and over expose the film before lightning strikes. If you have one of those gruesome, dark, ominous storms, than maybe it would work.

Although you may have caught something cool (probably not), the film has not progressed. Put your finger over the lens to ensure the film does not become further exposed, press the trigger, and wind the film wheel.

Place the camera down and try again. Unlike trying to snap lightning pictures on your digital camera with your non-lightning fast reflexes, this method should work every time. depending on how fast you can wind to the next frame.

Step 6: The Results

Remember to remove the string before returning for developing.

Like professional lightning photography, this wastes a lot of film. Out of 26 pictures I took, only 3 developed (which were of poor quality), which in hindsight wasn't too bad for the first attempt at a cheap, hacked method.

my second time at it was much more fruitful, with 11 out of 19 developing. One of the best from that set is shown in the intro.

Some tips:

1. Try to keep the camera as steady as possible. I think I'm going to try to make a clamp of some sort to hold mine down next time.

2. I wanted to catch some real bolts of lighting, so when distant lightning "flashed" and lit up the sky, I didn't close the shutter and waited for a good one. This over exposes the film. As soon as there is any significant light (any light with faster films) close the shutter. You'll be surprised: one time I did this, there actually was a little bolt in it I hadn't seen.

3. The best bolt will flash while you're progressing the film from a crappy shot. I swear it happened at least 4 times. Do this with a friend and make it into a competition, with each person getting every other flash. Afterwards you can take credit for the one he caught while you were winding your film.

4. If it doesn't work the first time, try again. These shots aren't too good, but I'll try again with what I've learned and post any progress.

If you have any luck with this method, send me the results, and I'll post them with due citation.